Automatic analyzers have a qualitative/quantitative analysis on blood, urine, and other biological samples in various ways. An example of its method is known to conduct the qualitative/quantitative analysis of samples by measuring the amount of light transmitted through a mixed reaction solution of the sample and a reagent, or by measuring the amount of light scattered by the reaction solution.
For example, Patent Document 1 (JP-2009-20059-A) discloses such an automatic analyzer, which employs a technique designed to determine whether a reaction cuvette for causing a reaction between a sample and a reagent and analyzing the sample can be actually used for measurement. Prior to the determination in this conventional technique, a reaction cuvette blank value that accretes with increasing changes in absorbance of a light beam transmitted through the reaction cuvette is compared with a plurality of determination criteria in which a different blank reference value is defined for each of analytical items. That is to say, the determination of the reaction cuvette for usability in the measurement is based primarily upon comparison results obtained from those comparisons.